Forming unit for machines for manufacturing welded pipes

ABSTRACT

Forming unit for machines for manufacturing welded pipes comprises one upright support for the forming roller support shafts on the drive side adapted to move in the direction of the shafts themselves, to engage and disengage itself from the roller support shafts, and a second upright supporting in a cantilever manner two pairs of forming roller support shafts extending in opposite directions, said second upright being adapted to be raised and rotate about itself through at least one half of a revolution.

United States Patent Corradini Aug. 26, 1975 [54] FORMING UNIT FOR MACHINES FOR 3,029,669 4/1962 McMartin 72/249 MANUFACTURING WELDED PIPES 3,796,081 3/1974 Boardman 72/181 Inventor: Remo Corradini, Guastalla, Italy 0. M. E. Officine Meccaniche Emiliane S.p.A., Guastalla (Reggio Emilia), Italy Filed: Aug. 12, 1974 Appl. No.: 497,117

Assignec;

Foreign Application Priority Data Mar. 8, 1974 Italy 42504/74 US. Cl. 72/179 Int. Cl B2ld 5/14 Field of Search 72/182, 181, 179, 238,

References Cited UNITED STATES PATENTS 1 1/1931 Simmons 72/226 Primary ExaminerMilton S. Mehr Attorney, Agent, or Firm-Brisebois & Kruger [57] ABSTRACT Forming unit for machines for manufacturing welded pipes comprises one upright support for the forming roller support shafts on the drive side adapted to move in the direction of the shafts themselves, to engage and disengage itself from the roller support shafts, and a second upright supporting in a cantilever manner two pairs of forming roller support shafts extending in opposite directions, said second upright being adapted to be raised and rotate about itself through at least one half of a revolution.

5 Claims, 5 Drawing Figures PAIENIED Aunesms sum 1 UF 4 PATENTED AUG 2 6 I975 SiliU 2 BF 4 NQE PATENTED AUG 2 6 I975 saw u 0F 4 FORMING UNIT FOR MACHINES FOR MANUFACTURING WELDED PIPES SUMMARY OF THE INVENTION Welded pipes are commonly formed in machines composed of a plurality of stations located in succession, each of which comprises two facing rollers of male and female shape which are arranged to give the strip a gradually increasing curvature until the strip is closed in the form of a pipe, and a station in which the two facing free edges of the plate already curved into the form of a pipe are welded by a continuous process.

These machines generally comprise a large number of forming stations, which in the initial machine section generally consist of a motorized unit from which extend two telescopic splined shafts coupled at their opposing ends by a suitable universal joint to two horizontal parallel shafts, of which the upper can be adjusted in level with respect to the fixed lower shaft.

These two shafts are supported at their respective ends by a fixed upright generally on the side of the re duction unit, and a mobile upright at the opposite end.

The mobile upright may move on a suitable slide and withdraw from the end of the two horizontal parallel shafts to enable the two male and female forming rol lers to be mounted and keyed on to these latter.

In the final machine section, where the curving of the pipe is completed, the forming rollers are both of concave shape, and are arranged laterally of the pipe to be formed, with their axes vertical.

Each forming machine for pipes of the aforementioned type is able to produce a large range of different diameters, each of which derives from a set of male and female forming rollers of different shape.

Because of the high speed with which the pipe is produced, the replacement of the forming rollers to equip the machine for forming pipes of a different diameter is a very frequent operation.

From the given description, it is immediately evident that, firstly, in known machines the equipping of the machine for producing a certain required pipe diameter has to take place with the machine at rest, and secondly, the time required for replacing the respective pair of male and female forming rollers in all the machine stations is very high, of the order of 6 7 hours.

In this respect, it is necessary to free each pair of shafts from one of the respective support uprights, withdraw the rollers mounted on them, mount and key the new rollers and reset the position of the support upright. This series of operations is repeated for each individual station.

If the diameter of the pipe being formed has to be changed frequently, the amount of down time necessary for setting up the machine becomes intolerable.

The object of the present invention is to provide a forming station of a type suitable for the aforementioned forming machines, in which the equipment designed for forming pipes of a certain diameter can be mounted during the operation of the station for forming pipe of a different diameter.

This is attained according to the invention, by making the upright support for the forming roller support shafts on the drive side movable in the direction of the shafts themselves, to engage with and disengage from the shafts, and causing the opposing upright to support in a cantilever manner two opposing pairs of forming roller support shafts, and capable of being raised and rotating about itself through at least one half of a revolution.

In this manner, when the station is operating with forming rollers of a certain diameter, two cantilever shafts are available laterally to it which can be equipped with forming rollers of a different diameter, without giving rise to down time.

The time for equipping the machine for forming pipes of different diameter is reduced to the time necessary for carrying out the following operations on each forming station included in the machine:

a. outward movement of the upright on the drive side to disengage the ends of the two cantilever shafts which carry the forming rollers b. raising, rotation through 180 and relowering of the opposing upright to bring the two new forming rollers previously mounted on the respective cantilever shafts into the machine path c. movement towards the machine centre of the upright on the drive side, to engage the drive unit with the ends of the two new forming roller support shafts.

The aforementioned operations enable the time necessary for equipping the machine for forming the new required diameters to be reduced to about one twentieth of the time formerly required.

The operational and constructional merits and characteristics of the invention will be more evident from the detailed description given hereinafter, which illustrates a preferred embodiment of the invention with reference to the figures of the accompanying drawings in which:

FIG. 1 is a partially sectional side view of a forming station in a pipe forming machine;

FIG. 2 is a plan view of the same station;

FIG. 3 is a partially sectional frontal view of the same station;

FIG. 4 is a plan view of the device for adjusting the level of the upper roller;

FIG. 5 is a section taken along the line VV of FIG. 4.

The said figures show that each individual forming station comprises a base 1, preferably common to all the forming stations. Said base 1 comprises at its top two horizontal parallel guides 2, on which a slide 3 can slide transversely with respect to the axis of the pipe being formed, the sliding movements being controlled in both directions by a double acting cylinder-piston unit 4.

Two vertical uprights 5 rise from the slide 3, and between them a slide 6 slides vertically, above a similar member 7 fixed to the base of the uprights.

The slide 6 and member 7 are hollow and define a cylindrical passage in which an internally splined sleeve 9 can freely rotate,supported by suitable roller bearings 8.

The ends of each sleeve 9 are connected through universal joints to shafts 10 connected to a geared motor drive unit 11 supported by a base parallel to the base 1.

The base 1 10 may also be common to all the forming stations present in the machine.

On the side opposite the two guides 2, the base 1 carries a locked cylinder-piston unit 12, operated hydraulically, the rod of which carries a member 13. Said member 13 is inserted and locked between two lateral locking guides 14 (see FIG. 3) when the rod of the cylinder-piston unit 12 is lowered.

The stroke of the cylinder-piston unit 12 is sufficient to raise the element 13 until it becomes disengaged from the two lateral guides 14, thus enabling it to freely rotate about the axis of the cylinder-piston unit.

Two lateral uprights l and a central upright 155 project upwardly from the member 13.

Two blocks 16 and 166 are locked between the lat eral uprights and the central upright 155, and each supports idle shafts 17 and 177 in a cantilever manner. These shafts extend in opposite directions with respect to the element 13.

The female forming rollers 20 are keyed on to the cantilever portion of the shafts 17 and 177.

In the upper part of the member 13 between the lateral uprights 15 and the central upright 155, two slides 21 and 221 slide vertically and comprise two blocks 42 and 422 analogous with the blocks 16 and 166. These two blocks also support two idle shafts 19, 199 in a cantilever manner, on to which are keyed the male forming rollers 22.

At the top of the uprights 5 and 15 there are suitable means for varying the height of the slides 6, 21 and 221, so as to regulate their distance from the fixed members 7, l6 and 166 in accordance with the diameter of the forming rollers.

For this purpose each of the slides 6, 21 and 221 is connected to the end of one of the threaded shafts 23, 24 and 25 respectively.

Said threaded shafts project from the centre of gear wheels 26, 27 and 28 respectively. The gear wheel 26 is engaged with a shaft 29 comprising a worm portion 30 and connected to the geared motor 31.

The shaft 29 terminates in an internally splined projecting sleeve 32.

The gears 27 and 28 are similarly engaged with two shafts 33 and 34 projecting in opposing directions from the support connected to the slide 13.

Said shafts terminate with two splined portions 35 and 36, each arranged for insertion and torsional locking in the sleeve 32.

The shafts 33 and 34 also carry hand wheels 37 and 38 respectively for manually controlling the small movements of the respective slides, the large initial level adjustments of the slides being made by the geared motor 31.

The operation of the forming station heretofore described is as follows. In the condition shown in FIG. 1, the station is set for forming pipes of a certain diameter, characterised by the shape of the rollers 20 and 22 keyed on the shafts 17 and 19.

Said shafts are rotated by the cardan shafts 10 by way of the splined sleeves 9.

During machine operation, the shafts 177 and 199 remain at the disposal of the operator, and on these he can key a different pair of male and female forming rollers, not shown in the figure.

To set the machine for forming pipes of different diameter, characterised by the shape of said second pair of rollers, the machine is stopped, the cylinder-piston unit 4 is then operated to move the slide 3 towards the left, so freeing the ends of the shafts 17 and 19 from the drive unit, together with the end of the upper adjustment shaft 29.

At this point, the cylinder-piston unit 12 is operated to raise the element 13, so freeing it from its locking shoulders 14.

The entire element 13 is rotated through to bring the shafts 177 and 199 with the relative new shaped rollers and the adjustment shaft 34 into the working position.

The element 13 is then lowered between the shoulders 14 to lock the entire assembly in position.

The subsequent movement to the right of the slide 3, driven by the cylinder-piston unit 4, inserts the ends of the shafts 177, 199 and 34 into the splined sleeves 9 and 32 respectively, so re-establishing the machine working conditions.

The invention is not limited to the single embodiment heretofore described, and modifications and improvements may be made to it without leaving the scope of the invention, the fundamental characteristics of which are summarised in the following claims.

What is claimed is:

1. In a unit for rolling strips into pipes, said unit comprising opposed male and female forming rollers, normally parallel shaft means removably carrying said rollers, a pair of uprights at opposite ends of said forming rollers in which said shaft means are rotatably mounted during rolling of said strip, and drive means connected to drive said shaft means, the connection between at least one of said shaft means and said drive means comprising a universal joint, the improvement according to which:

said drive means comprises a pair of telescopic members, a first upright nearest said drive means is movable longitudinally of said shaft means from a position supporting one end of each shaft means to a position clear of said shaft means while said drive members telescope, each of said shaft means projects from opposite sides of the other upright for a distance sufficient to enable it to support a forming roller, and said other upright is mounted to rotate about its vertical axis between a first position in which the shaft means projecting from one side of said other upright extend toward said first upright and a second position in which the shaft means projecting from the other side of said other upright extend toward said first upright.

2. Unit as claimed in claim 1 comprising means for raising and lowering said other upright and for locking it in either of its rotational positions when lowered.

3. Unit as claimed in claim 1 in which each of said uprights carries two transverse sleeves in which said shaft means are rotatably received when said unit is in strip rolling position.

4. Unit as claimed in claim 3 in which one sleeve carried by each upright is mounted for vertical movement relative to said upright.

5. Unit as claimed in claim 3 in which at least one of the sleeves mounted in said first upright is provided with internal splines which engage external splines on the shaft means received therein, and said splined sleeve is connected to be driven by said drive means. 

1. In a unit for rolling strips into pipes, said unit comprising opposed male and female forming rollers, normally parallel shaft means removably carrying said rollers, a pair of uprights at opposite ends of said forming rollers in which said shaft means are rotatably mounted during rolling of said strip, and drive means connected to drive said shaft means, the connection between at least one of said shaft means and said drive means comprising a universal joint, the improvement accordinG to which: said drive means comprises a pair of telescopic members, a first upright nearest said drive means is movable longitudinally of said shaft means from a position supporting one end of each shaft means to a position clear of said shaft means while said drive members telescope, each of said shaft means projects from opposite sides of the other upright for a distance sufficient to enable it to support a forming roller, and said other upright is mounted to rotate about its vertical axis between a first position in which the shaft means projecting from one side of said other upright extend toward said first upright and a second position in which the shaft means projecting from the other side of said other upright extend toward said first upright.
 2. Unit as claimed in claim 1 comprising means for raising and lowering said other upright and for locking it in either of its rotational positions when lowered.
 3. Unit as claimed in claim 1 in which each of said uprights carries two transverse sleeves in which said shaft means are rotatably received when said unit is in strip rolling position.
 4. Unit as claimed in claim 3 in which one sleeve carried by each upright is mounted for vertical movement relative to said upright.
 5. Unit as claimed in claim 3 in which at least one of the sleeves mounted in said first upright is provided with internal splines which engage external splines on the shaft means received therein, and said splined sleeve is connected to be driven by said drive means. 